Hey Since The Age Of 1yr Of Age, My 3yr

Hey Since the age of 1yr of age, my 3yr old son have these episodes of a persistent dry cough as if something is irritating his throat. Especially at night he cough all night. He does not wheeze or has difficulty breathing when this happen. I am giving Prospan syrup, Venteze+Actifed mixture and Texa allergy suryp. I rub his chest with Vicks Vapo rub but never tried rubbing his feet. At times I use the nebulizer @ gives Duolin and another ampule just cant get to the name. All of these does not give much relief. Please give advise. I had him @ a new GP on Saturday and he said it is tonsilitis because his throat is red. but I know it is not tonsilitis, the hard irritating cough causes the throat to be red.